html_material_panels = html_material_panels or {}

function ClearCustomMaterials()
    for key, pnl in pairs(html_material_panels) do
        if pnl:IsValid() then
            pnl:Remove()
        end
    end

    html_material_panels = {}
end

function GetCustomMaterial(url, callback)
    local pnl= vgui.Create("HTML")
    table.insert(html_material_panels, pnl)
    pnl:OpenURL(url)
    pnl:Refresh()
    pnl:SetSize(100, 100)
    pnl:StartAnimate()
    --pnl:SetPos(ScrW(),ScrH())
    function pnl.FinishedURL()
        callback(pnl:GetHTMLMaterial())
    end
end

ClearCustomMaterials()

GetCustomMaterial("http://www.google.com", function(mat)
    local ent = Entity(646)

    function ent:RenderOverride()
        render.SetMaterial(mat)
        self:DrawModel()
    end
end)